Matthew W. Nonnenmann

Dust in Pig Buildings

It is well documented in the international scientific literature that airborne dust in pig houses can cause serious health problems for humans as well as for animals. Extensive research has been carried out in different countries during the last few decades to improve the scientific understanding of air quality issues related to intensive animal production. Research and review papers were presented at the international symposium on Dust Control in Animal Production Facilities, held in Denmark in 1999. Different techniques have been used in order to reduce dust burdens in pig confinement buildings, but up to date only the procedure of spraying oil or a mixture of oil and water has contributed to reducing the indoor dust concentrations significantly. This article summarizes the current level of understanding of dust issues in intensive animal production buildings, mainly on the basis of papers presented at the above-mentioned symposium.

Culture-Independent Characterization of Bacteria and Fungi in a Poultry Bioaerosol Using Pyrosequencing: A New Approach

Work in animal production facilities often results in exposure to organic dusts. Previous studies have documented decreases in pulmonary function and lung inflammation among workers exposed to organic dust in the poultry industry. Bacteria and fungi have been reported as components of the organic dust produced in poultry facilities. To date, little is known about the diversity and concentration of bacteria and fungi inside poultry buildings. All previous investigations have utilized culture-based methods for analysis that identify only biota cultured on selected media. The bacterial tag-encoded flexible (FLX) amplicon pyrosequencing (bTEFAP) and fungal tag-encoded flexible (FLX) amplicon pyrosequencing (fTEFAP) are modern and comprehensive approaches for determining biodiversity of microorganisms and have not previously been used to provide characterization of exposure to microorganisms in an occupational environment. This article illustrates the potential application of this novel technique in occupational exposure assessment as well as other settings. An 8-hr area sample was collected using an Institute of Medicine inhalable sampler attached to a mannequin in a poultry confinement building. The sample was analyzed using bTEFAP and fTEFAP. Of the bacteria and fungi detected, 116 and 39 genera were identified, respectively. Among bacteria, Staphylococcus cohnii was present in the highest proportion (23%). The total inhalable bacteria concentration was estimated to be 7503 cells/m 3 . Among the fungi identified, Sagenomella sclerotialis was present in the highest proportion (37%). Aspergillus ochraceus and Penicillium janthinellum were also present in high proportions. The total inhalable fungi concentration was estimated to be 1810 cells/m 3 . These estimates are lower than what has been reported by others using standard epifluorescence microscope methods. However, no study has used non-culture-based techniques, such as bTEFAP and fTEFAP, to evaluate bacteria and fungi in the inhalable fraction of a bioaerosol in a broiler production environment. Furthermore, the impact of this bTEFAP and fTEFAP technology has yet to be realized by the scientific community dedicated to evaluating occupational and environmental bioaerosol exposure.

Musculoskeletal symptoms of the neck and upper extremities among Iowa dairy farmers

BACKGROUND The prevalence of musculoskeletal symptoms (MSS) among U.S. dairy farmers is relatively unknown. The purpose of this study was to assess the prevalence of neck and upper extremity MSS, and to examine associations between symptoms and dairy operation activities among dairy farmers. METHODS Questionnaires were mailed to randomly selected dairy farmers in the State of Iowa, USA. Demographic, site specific MSS, and dairy operation activity information was obtained. Odds ratios and 95% confidence intervals were estimated with logistic regression adjusting for potential confounders. RESULTS Among the participants (N = 341), shoulder MSS were reported most frequently (54%). Neck MSS were significantly associated with manually feeding (OR(adj) = 2.29; 95% CI = 1.09-4.80) and tractors use (OR(adj) = 2.17; 95% CI = 1.05-4.50). Also, wrist/hand MSS were associated with manually cleaning animal stalls (OR(adj) = 1.96; 95% CI = 1.06-3.63). CONCLUSIONS Neck and upper extremity MSS were common and associated with common dairy farming practices. Future studies need to more accurately assess exposures to physical risk factors for MSS so ergonomic interventions can be developed.

Full shift arm inclinometry among dairy parlor workers: A feasibility study in a challenging work environment

Over the last 20 years, the US dairy industry has experienced a significant transformation from small farm operations to an industrialization of the milking process. This transformation has resulted in improvements in process efficiency and product quality. Milking tasks in large-herd parlors are highly-repetitive involving awkward postures and high muscle loads of the upper extremity. Field-based direct measures of physical exposures have been limited in challenging work settings such as dairies. This study evaluated full-shift exposures of posture and motion of the upper extremity among large-herd parlor milkers using wireless inclinometry. Results suggest large-herd parlor workers may be exposed to high exposure levels (posture, movement velocity, repetition, and inadequate rest) associated with the development of shoulder pathology. Compared to other high-risk occupations involving shoulder-intensive work, parlor workers may have higher exposure levels. These findings warrant the need for continued field-based research with larger sample sizes to facilitate the development of cost-effective intervention strategies.

Systematic Review of Respiratory Health Among Dairy Workers

ABSTRACT The dairy industry is changing on a global scale with larger, more efficient operations. The impact of this change on worker health and safety, specifically, associations between occupational lung disease and inhalation exposures, has yet to be reported in a comprehensive review of the scientific literature. Therefore, a three-tier process was used to identify information using a keyword search of online databases of scientific literature. Of the 147 citations reviewed, 52 met initial screening criteria, and 30 were included in this review. Dairy workers experience lung conditions such as asthma, chronic obstructive pulmonary disease, hypersensitivity pneumonitis, chronic bronchitis, and cancer. Recent pulmonary function studies have identified obstructive lung changes among dairy farm workers. The increased scale of dairy production with significant changes in technology and work practices has altered inhalation exposure patterns among dairy workers. The inhalation exposure in the dairy work environment may elicit differing inflammatory responses in relation to timing of initial exposure as well as to repeated exposures. Few studies have measured inhalation exposure while simultaneously assessing the impact of the exposure on lung function of dairy farm workers. Even fewer studies have been implemented to assess the impact of aerosol control technology to reduce inhalation exposure. Future research should evaluate worker exposure to aerosols through a task-based approach while utilizing novel methods to assess inhalation exposure and associated inflammatory responses. Finally, potential solutions should be developed and tested to reduce inhalation exposure to inflammatory agents and respiratory diseases in the dairy farm work environment.

Factors influencing safety among a group of commercial fishermen along the Texas gulf coast

ABSTRACT The commercial fishing trades are among the most dangerous jobs in the world. Little published information exists regarding some populations of commercial fishermen such as along the United States Gulf Coast. Studying these unique and often vulnerable groups is important to characterize potential influences on or barriers to safety in anticipation of designing interventions that can change safety behaviors. Working closely with the United States Coast Guard (USCG), a cross-sectional convenience sample of Gulf Coast shrimp fishermen in and near the Port of Galveston, Texas, was surveyed. The survey included demographic factors and broadly covered areas such as type of work and fishing activities, general or global perceptions and beliefs related to safety and accidents, self-report of ability to use safety equipment or apply procedures aboard vessel, and training considerations. Surveys were obtained following informed consent (n = 133). Of the participants, 96.7% were male with 60.9% ≥40 years old. A majority were of Asian descent (57.1% of all fishermen, 82.1% of shrimp fishermen). Over half claimed to speak little or no English and nearly 60% considered the job to be very safe to neutral. A third to half of respondents expressed doubt about their knowledge of using essential safety equipment in the event of emergency. A large portion of the participants preferred hands-on safety training (40.6%). Important findings about this group of commercial fishermen will help with future development of effective prevention practices through the delivery of culturally appropriate safety awareness training. One element that must be addressed in training programs is to increase the awareness among fishermen about the severe occupational risks inherent in this type of work. Community trust and collaborative partnerships are essential to the success of such initiatives.

Utilizing pyrosequencing and quantitative PCR to characterize fungal populations among house dust samples

Molecular techniques are an alternative to culturing and counting methods in quantifying indoor fungal contamination. Pyrosequencing offers the possibility of identifying unexpected indoor fungi. In this study, 50 house dust samples were collected from homes in the Yakima Valley, WA. Each sample was analyzed by quantitative PCR (QPCR) for 36 common fungi and by fungal tag-encoded flexible (FLX) amplicon pyrosequencing (fTEFAP) for these and additional fungi. Only 24 of the samples yielded amplified results using fTEFAP but QPCR successfully amplified all 50 samples. Over 450 fungal species were detected by fTEFAP but most were rare. Twenty-two fungi were found by fTEFAP to occur with at least an average of ≥0.5% relative occurrence. Many of these fungi seem to be associated with plants, soil or human skin. Combining fTEFAP and QPCR can enhance studies of fungal contamination in homes.

Prevalence of work‐related musculoskeletal symptoms among US large‐herd dairy parlor workers

BACKGROUND Dairy production in the US is moving towards large-herd milking operations resulting in an increase in task specialization and work demands. METHODS A modified version of the Standardized Nordic Questionnaire was administered to assess MSS prevalence among 452 US large-herd parlor workers. Worker demographics and MSS prevalences were assessed, and differences based on parlor configuration (i.e., herringbone, parallel, rotary) were computed. RESULTS Three-fourths (76.4%) of parlor workers reported work-related MSS in at least one body part. Highest prevalences were reported in the upper extremity (55%). Herringbone workers reported a higher prevalence of MSS in the wrist/hand, and rotary workers reported higher prevalences of MSS in the neck, upper back, and shoulders. CONCLUSIONS Our findings draw attention to higher work-related MSS in the upper extremity among dairy parlor workers. As the trend toward larger herd sizes on US dairy farms continues, the need for further health and safety research will increase.

Work-Related Injuries and Fatalities on Dairy Farm Operations—A Global Perspective

ABSTRACT Agriculture is among the most hazardous sectors for workers globally, and dairy farming has been associated with a high risk of injury among workers in several countries. The purpose of this paper is to provide an update on what is known about modern dairy farms and related injuries and fatalities in different regions of the world. As in other sectors of agriculture, fatalities appear to be associated with heavy equipment usage, whereas injuries occur at higher rates with animal production, specifically cattle and milk production. Dairy farming is associated with higher rates of injury as compared with other industrial sectors, but a lack of work-related injury reporting continues to be an issue in several countries. Worker fatality associated with heavy equipment use is not a new observation (e.g., tractors); however, manure-handling systems, livestock handling, and quad bike operation continue to be associated with worker injuries and fatalities on modern farms. Opportunities exist for improvement of safety-related equipment to reduce injury and fatality risk during worker interactions with large animals and farm equipment.

Field and Wind Tunnel Comparison of Four Aerosol Samplers Using Agricultural Dusts

Occupational lung disease is a significant problem among agricultural workers exposed to organic dusts. Measurements of exposure in agricultural environments in the USA have traditionally been conducted using 37-mm closed-face cassettes (CFCs) and respirable Cyclones. Inhalable aerosol samplers offer significant improvement for dose estimation studies to reduce respiratory disease. The goals of this study were to determine correction factors between the inhalable samplers (IOM and Button) and the CFC and Cyclone for dusts sampled in livestock buildings and to determine whether these factors vary among livestock types. Determination of these correction factors will allow comparison between inhalable measurements and historical measurements. Ten sets of samples were collected in swine, chicken, turkey, and dairy facilities in both Colorado and Iowa. Pairs of each sampling device were attached to the front and back of a rotating mannequin. Laboratory studies using a still-air chamber and a wind tunnel provided information regarding the effect of wind speed on sampler performance. Overall, the IOM had the lowest coefficient of variation (best precision) and was least affected by changes in wind speed. The performance of the Button was negatively impacted in poultry environments where larger (feather) particulates clogged the holes in the initial screen. The CFC/IOM ratios are important for comparisons between newer and older studies. Wind speed and dust type were both important factors affecting ratios. Based on the field studies (Table 6), a ratio of 0.56 is suggested as a conversion factor for the CFC/IOM (average for all environments because of no statistical difference). Suggested conversion factors for the Button/IOM are swine (0.57), chicken (0.80), turkey (0.53), and dairy (0.67). Any attempt to apply a conversion factor between the Cyclone and inhalable samplers is not recommended.